Retaining Walls

Design Engineering has a long history of providing engineering consultation for retaining walls for residential, commercial/industrial, and subdivisions sectors with more than 30 years of local building experience in Perth. Working to an international quality management standard (ISO 9001-2015), we are able to offer our services with the highest level of quality control which can be difficult to find elsewhere. All engineering drawings and calculations are checked in-house by our highly qualified and experienced team to ensure all quality procedures are adhered to.


Types of Retaining Walls

Design Engineering has experience in designing, providing certifications and conducting retaining wall inspection in Perth for the following types of retaining walls:

Cantilevered type retaining walls

These commonly consist of masonry block units with internal steel reinforcement or in-situ/precast reinforced concrete. The walls are generally thin compared to gravity type walls but are attached to a large footing. The internal reinforcement provides the strength required for the wall to act as a beam and cantilever from the base. The large base provides the lateral/rotation restraint required to resist the loads. Typical applications for these walls include basement walls, fencing and bund walls. The walls can be used to retain earth or liquids or a combination of both with or without surcharges.

Cantilevered type retaining walls

Gravity type retaining walls

These depend on their mass to resist the loads rather than their strength. They are commonly made from limestone blocks, masonry blocks, mass concrete or gabions baskets. They generally have a batter which improves their stability. Typical applications for these walls include large subdivisions walls and landscaping walls. The walls can be used to retain earth or liquids or a combination of both with or without surcharges.

Gravity type retaining walls

Sheet pile retaining walls

These generally consist of steel sheeting which is driven into the ground. This type of wall is used primarily where space is limited and soil conditions are inadequate to support other types of walls. Between 30-50% of the pile is embedded which provides the lateral and rotational restraint. Typical applications for these walls are for excavations, and soil stabilisation purposes.

Sheet pile retaining walls

Post and panel retaining walls

These consist of a post driven into the ground at determined intervals with panels attached above ground to resist loads behind the wall. They are a form of cantilever wall, however, they do not rely on a footing to provide lateral and rotation restraint; the restraint is provided by the embedment of the post. Typical applications for these walls are for residential and commercial purposes.

Post and panel retaining walls

Soil Grouting

This can be used to stabilise the soil locally by injecting a grout or cement into the sand so that it acts as a large unit. This is usually performed during construction stages of a project to stabilise soil while other works are proceeding or to improve the stability of soil where other wall types cannot be used due to confined spaces.

Retaining Wall Council submission

Is certification for council submission required? Our structural engineering team can assess a current retaining wall to see whether it can sustain the proposed building or certify that it has been constructed structurally sound.

When a Structural Engineer is Required for Retaining Walls?

Retaining walls are commonly used in Perth, especially in residential subdivisions and land development. If construction follows certified structural engineering drawings, there should be no issues with the wall’s performance or durability.

However, omission of minor details can lead to costly rectification works. Visible signs of leaning, cracking, movement, or bulging can indicate structural failure, especially if the wall supports additional structures like houses. If concerns arise, a professional structural engineer should inspect the wall and provide a written report on its structural adequacy.

Always check with your local council for requirements and specifications to your area, as they likely differ. Many councils however, do require that retaining walls are designed by a structural engineer. This means that council applications need to be accompanied by a signed structural engineer’s drawings.

How We Can Help with Your Retaining Walls?

At Design Engineering, we provide a diverse approach to building retaining and screen walls, ranging from modest garden beds to larger support structures. Whether you want certification for a retaining wall, routine information for a basic project, or more complicated specifications, our structural engineers with expertise in dealing with various materials and pre-cast systems ensures that your project is in capable hands.

Design and Drawings

Here at Design, our capabilities include analysis of the soil and providing the stability and strength calculations for the wall. Our designs are fully compliant with the Building Code of Australia and relevant Australian standards including AS 1170 series, AS 2870, AS 3600, AS 4100, AS 3700, AS 2159, AS 4678 and many others. Our in-house drafting team are able to provide engineering drawings to the highest standard in compliance with the requirements of AS 1100.

Structural Certification and Approvals

A structural engineer’s certificate of compliance is recommended and sometimes mandatory for building a retaining wall. The team can certify the project after assessing the proposed plan or applying amendments to ensure compliance with development standards. The higher the wall, the greater the risk.

Consult a structural engineer to ensure safety and durability. Permission and certification depend on the location, local government regulations, and design certification. In WA, the wall must not exceed 500mm, otherwise, it needs to be certified by an engineer before construction. The general rule is to consult a structural engineer for safety and durability.

Construction Supervision

Our engineers have experience supervising the construction of the retaining wall types detailed above. We are able to provide the required documentation including non-compliance reports and QA sheets for concrete strength, block strength, mortar strength and soil compaction test results to ensure the walls are constructed as per the contract drawings.

Retaining walls

Please send through your enquiry today via email to info@designeng.com.au and we will call you to discuss your project.